There is also the book by Brotzman (Old Testament Textual Criticism, 1994 or 2016 edition with Tully) that has many of the abbreviations and walks through all textual criticism of the book of Ruth in BHS, if you want to see it in action. Then there is the Jonah Handbook by W. Dennis Tucker (Baylor, 2006) that should help with Jonah in BHS. Or Robert Chisholm (A Workbook for Intermediate Hebrew), which can help more with parsing and syntax practice of Jonah and Ruth alike.

Thank you for your great resource! But I'm still struggling because of the transliterations in the BHS Apparatus. They are a bit different from English transliteration I learned. For example, I'm looking at Samuel I 16:7 b. In Syriac the transliteration is b'jn'(pl), Targum b'jnjhwn and c. in Syriac blb'.

Can you help me where I can find how to decode the transliteration in BHS Apparatus?